Cercarial shedding of trematodes and their associated snail intermediate hosts in Borno State, Nigeria

Abstract

ObjectiveTo determine the distribution of cercariae of trematodes and their associated snail intermediate hosts in Borno State, Nigeria. MethodsHandpicking and scooping by the aid of scoop nets were used to collect a total of 1 700 snails. They were examined for cercarial release using emergent method of cercarial release. Results16 (0.94%) of the 1 700 snails were positive for cercariae of trematodes based on morphology and standard measurement. Three species (Bulinus forskalli, Bulinus globosus and Lymnae natalensis) of snails were identified based on shell morphology and standard criteria. Distribution of the infection among the sampled snails showed that, 10 (1.75%) of Bulinus globosus and 6 (0.55%) of Lymnae natalensis released cercariae of Schistosoma haematobium and a distome cercaria of Fasciola spp. respectively. The intensity of infection among the examined snails varied significantly (P<0.05) based on senatorial zones of sampling. ConclusionsThe present study has demonstrated the presence of some important trematodes and snail species that are possible intermediate hosts in Borno State. This study will further provide insight into better understanding of the epidemiology of schistosomiasis caused by Schistosoma haematobium and other trematodes and the role of snails (Bulinus globosus and Lymnae natalensis) as intermediate hosts.